I can share with you three generations of self-knowledge tools I rely on since 1994.
Generation 1 was none other than a daily journal to keep track of my ambitions, thoughts, ideas. The journal delivered all the benefits writing brings in this context including more confidence, clarity and a sense of purpose. I can't say any single day's journal delivered an 'a-ha' moment however. Instead I feel the process of keeping journals day-over-day, year-over-year were instrumental gradually building my know-how in any one particular area of interest.
Generation 2 tools were more deliberate and represented a process of setting objectives and planning ways to achieve them at the start of the year and then journaling action/progress over the course of the year. Here also i cannot say 'a-ha' moments came as a result of any one thing. Instead, re-reading previous year's objectives, and the experience in trying to achieve them, was probably effective in gradually building know-how for future plans.
In generation 3, the tools are enabling the data-driven, near-real time self-tracking I am currently doing. Here there have been more 'a-ha' moments as a direct result of the descriptive/explanatory analysis performed on the data collected. This is expected considering generation 3 tools collect, analyze and output structured data (as opposed to semi-structured natural language text from Gen 1 +2 tools).
I suppose an opportunity for a generation 4 set of tools is to focus on implementing a similar descriptive/explanatory/predictive analysis against the gen 1+2 journal text! - this would produce more 'a-ha' insights from the data collected in Gen 1 and 2.
Hope this helps.